Semiconductor electronic devices are made in foundries, of which there are over a hundred worldwide (operated by approximately two dozen or so semiconductor companies adopting a foundry model). Fabrication of large-scale integrated semiconductor electronic devices requires multiple process steps and mask layers that define etching and deposition patterns (e.g., for photoresists), dopant implants, and metallization. A semiconductor foundry may employ a particular set of process steps and mask layers for a given semiconductor device, and process steps/mask layers can differ significantly for different types of semiconductor devices (as well as similar devices made by different foundries). A particular set of process steps and mask layers employed by a given foundry to fabricate any of a variety of semiconductor devices is generally referred to as a “semiconductor manufacturing process technology” (or simply “semiconductor technology”). For fabrication of silicon-based Complimentary-Metal-Oxide-Semiconductor (CMOS) devices, different manufacturing process technologies are sometimes commonly referred to as “CMOS technology nodes.” Some common examples of conventional CMOS technology nodes include a 45-nm silicon-on-insulator (SOI) process technology available from IBM (i.e., the IBM SOI12S0 45-nm technology), as well as the IBM SOI13S0 32 nm technology and the IBM 10LPE technology.
One area of developing research in computing relates to monolithic integration of million-to-billion-transistor circuits with photonic components as an enabling technology for high performance computers (HPC). Generally speaking, “photonic components” refer to various devices employed for light (or photon) generation or emission, transmission or propagation, modulation (e.g., signal processing, switching, filtering, wavelength and/or mode selectivity, amplification), and detection. Optical processing techniques enabled by photonic components can accelerate computation in HPCs by performing processor-intensive tasks at significantly faster rates and with a significant reduction in energy consumption as compared to purely electronic processing techniques. Accordingly, the integration of photonic components and electronic components for computing and other applications is an active area of research endeavor.
In connection with photonic detection devices (referred to generally as “photodetectors”), some investigated approaches for design and fabrication of photodetectors rely on specialized materials, processes and/or geometries that are particularly useful for fabrication of photonics components, but generally are not readily available in conventional semiconductor manufacturing process technologies employed in advanced electronic foundries. Moreover, the modifications required of conventional semiconductor technologies to accommodate photonic components generally involve costly process development that in turn creates challenges in maintaining fabrication yield.